I just got this for my ps2.... it saddens me to say it as I still love MLB Power Pros but - this game absolutely rocks. The 'Road to the Show' (Career) mode is incredibly fun and for the first time in I don't know how long.... the announcers seem like they know what's going on! About once per game they screw something minor up, but it's not every other play. (aka: They don't incorrectly announce things all the time like they do in MLB 2k8/2k7, MLB Power Pros, etc)
Anyways, for those of you with PS2 consoles - this is definitely worth checking out. It's only out for PS2, PSP, and PS3 as far as I know. PS3 version is obviously the best for the graphics, but the PS2 version still looks damn nice.
MLB 08: The Show (8.7)
http://ps3.ign.com/articles/856/856121p1.html
Kind of funny when compared to 2k8's 7.2 rating...
http://ps3.ign.com/objects/898/898263.html